ESP32-C3

[中文]

The ESP32-C3 supports two ways to download the firmware: UART0 and USB.

Hardware Connection

When you are use the UART0 pins to download the firmware ,the following wiring conditions need to be satisfied:

VDD     -> 3V3
GND     -> GND
EN      -> Pull Up    (Used for power on Control, can't be float)
GPIO2   -> Pull Up     (Controls the SPI Flash startup mode)
GPIO8   -> Pull Up
GPIO9   -> Pull Down   (Enter download mode)
TXD0(GPIO21)    -> RX
RXD0(GPIO20)    -> TX

When you are use the USB pins to download the firmware ,the following wiring conditions need to be satisfied:

VDD     -> 3V3
GND     -> GND
EN      -> Pull Up    (Used for power on Control, can't be float)
GPIO2   -> Pull Up     (Controls the SPI Flash startup mode)
GPIO8   -> Pull Up
GPIO9   -> Pull Down   (Enter download mode)
GPIO18  -> USB_D-
GPIO19  -> USB_D+

Note

  • After powering up the chip/module, you can verify whether it has entered Download Boot mode by using the UART0 serial port.

  • The strapping combination of GPIO8 = 0 and GPIO9 = 0 is invalid and will trigger unexpected behavior.

Hardware conditions must be met

  • ESP32-C3 chip working voltage range is 3.0 V ~ 3.6 V; if you use a single power supply, the recommended voltage of the power supply is 3.3 V, and its recommended output current is 500 mA or more.

  • ESP32-C3 modules working voltage range is 3.0 V ~ 3.6 V; if you use a single power supply, the recommended voltage of the power supply is 3.3 V, and its recommended output current is 500 mA or more.

Reference

Summary of Hardware Wiring Principles:

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